{"id":557178,"date":"2024-11-05T18:17:13","date_gmt":"2024-11-05T18:17:13","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/esdu-000242011\/"},"modified":"2024-11-05T18:17:13","modified_gmt":"2024-11-05T18:17:13","slug":"esdu-000242011","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/esdu\/esdu-000242011\/","title":{"rendered":"ESDU 00024:2011"},"content":{"rendered":"<p>\n\tESDU 00024 introduces a computerised method for estimating the<br \/>\nsound power attenuation of absorbent linings in constant section<br \/>\nstraight rectangular ducts with axial flow. The method is based on<br \/>\na theoretical model that takes the velocity profile across the<br \/>\nduct, assumed constant axially, into consideration. The method can<br \/>\nalso be applied to annular ducts with inner radius to outer radius<br \/>\nratios as low as 0.5, below which the risk of error increases. Up<br \/>\nto ten duct sections with different linings in each can be<br \/>\nconsidered. The program, ESDUpac A0024, permits the user to output<br \/>\nresults at third-octave band centre frequencies, at specified<br \/>\nfrequencies, or over a frequency range with constant step increment<br \/>\nbetween the frequencies. Equal energy in each mode or equal<br \/>\namplitude in each mode can be selected. Individual modes can be<br \/>\nweighted. The output can be total attenuation at each frequency, or<br \/>\nthe total attenuation and the attenuation in each mode at each<br \/>\nfrequency. The format of the input file is explained and a second<br \/>\nESDUpac, B0024, facilitates its construction. The input requires<br \/>\nvalues for the normalised acoustic impedance for each lined section<br \/>\nand, for low Mach numbers, values may be taken from ESDU 74003 and<br \/>\n74004, while for higher Mach numbers, the manufacturer&#039;s values<br \/>\nwill need to be used. Worked examples illustrate the various<br \/>\nfeatures of the program.\n\t<\/p>\n","protected":false},"excerpt":{"rendered":"<p><b>The Acoustic Attenuation of Absorbent Linings in Rectangular Flow Ducts with Application to Annular Flow Ducts<\/b><\/p>\n<table style=\"width: 100%\" border=\"0\" cellspacing=\"0\" cellpadding=\"0\">\n<tbody>\n<tr>\n<td>Published By<\/td>\n<td>Publication Date<\/td>\n<td>Number of Pages<\/td>\n<\/tr>\n<tr>\n<td><a href=\"https:\/\/pdfstandards.shop\/product-category\/publishers\/esdu\/\"><b>ESDU<\/b><\/a><\/td>\n<td>2011-03<\/td>\n<td>NA<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":0,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[2675],"product_tag":[],"class_list":{"0":"post-557178","1":"product","2":"type-product","3":"status-publish","5":"product_cat-esdu","7":"first","8":"instock","9":"sold-individually","10":"shipping-taxable","11":"purchasable","12":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/557178","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=557178"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=557178"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=557178"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}